Commutator tube device



ep 1953 1.. BATCHELDER 2,654,040

I COMMUTATOR TUBE DEVICE Filed Nov. 21, 1947 2 Sheets-Sheet 1 luvs/whiz (Al/Raves 84mm DER .dr'mnusv Patented Sept. 29, 1953 COMMUTATOR TUBE DEVICE Laurence Batchelder, Cambridge, Mass., assignor to Raytheon Manufacturing Company, a corporation of Delaware Application November 21, 1947, Serial No. 787,441

16 Claims.

The present invention relates to electron tube devices for commutation of electric current in successive different circuits, and in particular to an improved system of electron beam direction control for such tubes.

In copending application Serial No. 655,447, filed March 19, 1946, there is disclosed a commutator tube employing a cathode, an accelerator anode positioned near the cathode, a plurality of commutator electrodes positioned near the anode on the other side from the cathode, means for forming the electrons from th oathode into a beam which has two parts that extend in opposite directions from the cathode, and means for sweeping one end of the beam along the anode to contact successive commutator electrodes. The accelerator anode is provided with an elongated aperture and the beam has one end more or less focussed in the aperture, the other end being intercepted by an unapertured portion of the anode. In a practical embodiment the anode is cylindrical and concentrically surrounds the cathode, and the aperture is a circumferential slot therein, whil the commutator electrodes surround the anode adjacent the slot. The beam-forming means comprises at least one pair of dissimilar magnetic poles positioned outside the tube on a line extending diametrically through the tube and passing through the anode and certain of the commutator electrodes. The resultant electron beam is diametrically disposed and has two ends at opposite ends of the diameter. Various means for rotating the eifective position of the magnetic poles about the axis of the tube may be employed. The anode in such embodiments is slotted circumferentially for only 180 degrees, for, while on end of the beam is available for current commutation, the other end must be masked or intercepted by unslotted anode material to avoid confusion as to which end is in use. As a consequence, commutator electrodes are useable for only 180 degrees of the available space around the anode in the tube. To provide a tube having commutator electrodes in the entire 360 degrees of available space, an embodiment having in efiect two cathodes and an anode with two diametrically opposed 180 degree slots, one for each resultant electron beam, is proposed in said application. This embodiment requires additional grid control means for the beams for best performance. I

The present invention has as its major object to improve on the aforementioned and similar devices by providing a commutator tube wherein the accelerating anod has an aperture extending a full 360 degrees about the cathode, and means whereby one end only of a single two-ended electron beam from the cathode is employed to contact commutator electrodes disposed completely about the anode.

Another object is to provide a commutator tube device of the aforementioned or similar kind wherein the two portions of the beam can be so directed that one end of the beam lies in the plane of the anode aperture and the other end lies in another plane.

Another object is to provide such a commutator tube device having reliable and relatively simple means for directing and rotating the beam.

Still another object is to provide such a device that will take up a minimum of space and be of the lightest possible weight.

Yet another object is to provide a device having the above new features without interfering with the operation with regard to features already in use. Thus, the device of the present invention provides inherently smooth commutation at practically any desirable commutation speed, and is as fully adaptable to use in various circuits as are prior devices, with the additional improvement that more circuits can be handled with a minimum increas in complexity.

Other and further objects and features of the invention will become apparent from the description of certain embodiments thereof that follows, reference being made to the accompanying drawings, wherein:

Fig. 1 shows a side elevation partially in section of a device in accordance with the invention; I

Fig. 2 shows a top view of the embodiment of Fig. 1;

Fig. 3 shows a side elevation partially in section of another embodiment of the invention;

Fig. 4 shows a top view of the embodiment of Fig. 3;

Fig. 5 shows an end view of the same embodiment; and

Fig. 6 shows a typical circuit connection for the commutator tube shown in the other figures.

In Figs. 1 and 2, there is shown an electron tube I0 having an envelop II which is preferably evacuated or contains a small amount of an inert gas. The envelope is mounted on a base 12 to which there is sealed a press [3 of well-known form through which certain wires communicate with the interior of the envelope and on which certain of the tube elements are mounted. The tube elements comprise in part a thermionic cathode l4 and a cylindrical anode 15, made in two parts [6 and I? which are coaxially disposed endwise with a slot-shaped apertur I 8 between them extending a full 360 degrees about the anode. Th cathode I4 is disposed within the lower anode portion 16 only, being supported on a conductor 21, which is sealed through the base l2 and press 13. It may b indirectly heated by any well-known heating means, not shown. The lower anode portion I6 is supported in the press 13 by means of supports IQ, of which one extends through the base I2 for the purpos of making an electrical con nection, while the upper portion I1 is supported by a conductive rod 2| sealed through the top of the envelope l l and provided exteriorly thereof with an electrical connector 22 of the form commonly known as a grid eap. Themed- 21.; may be attached to the upper anode portion l-I =by means of a conductive cross-arm 20. Other means of supporting the arwdesectiops maybe employed if desired, it being necessary for smooth commutation, however, that the slot l8 be uninterrupted for its entire circumferential length. Surrounding the anode -15 is a nonconductive cylinder 23, which may be'made of glass, to the interior side of which-are attached conductive strips- 24 which have the function of commutae tor electrodes. These strips may bemade of silver sputtered onto the glass-andseparated by scratching away or-otherwise removing hair-thin portions of the silverat desired intervals to space the strips closely -apart.- The non-conductive cylinder is supported in the press bysupports 25 sealed to-the cylinder and into the press, and a conductor 26 isattached-to-eachcommutator strip 24 and brought out of the tube through thebasel2. -The electron'stream fromthe cathode to the anode I is formed-into-a pair of oppositelydirected narrow radial-beams, not shown, by means of a four-pole electromagnetic resolver of a well-known form having uniformly distributed pole pieces 3|, 32,-33 and 34,-each ofwhichis provided with an individual energizing coil 35, 3B, 31 and 38, respectively. -The-core structure of the resolver is preferably laminated-asshown in Fig. 1. The coils 35 '383'11'101113116; maybe energized in a well-known 'manner fromany known kind of source 0% alternatingcurrent which provides voltages at the sameirequency in phase quadrature to the respective-coils. The pole pieces 3| to 35, inclusive,- are thereby energized so that diametrically opposed faces, for example N and S, have dissimilar magneticpolarities. *As 'iswell known, the resolver 30 ..will, when energized in this manner, rotate the electron beams aboutthe axis of the cathode M-to sweep the beam-endscircumferential-ly around the --interior ofthe anode A5. The-beams will then lie at any time along a diameter ofthe cylindrical anode within the-lower-portion [6, with both ends in the same transverse-plane...

ln-the presentembodiment of the invention,

thebeams areutiltedawith respect..to..a plane transverseto. the anode .15, the direction of. tilt being towardv parallelism withutheaxis of the anode, sothatthe beams .are directedas shown by the dot-dashed line lfl andone. endof the beams lies in the slot. l8 while the other end is totally,.inter.cepted .by anode, material, .here by the lower portion. Hi. The tilting is .accom-. plished by applying. an additional component of magnetic flux parallel to the. axis of .thetube ill. with an additional coil. .whichis disposed about the tube as a: solenoid wound about .the axis of the tube. This coil 4| maybeenergized from any suitable source of unidirectional current. by. 6911: nection to the ends |2 and A3. The .magnitude of ,,the direct current. potential applied to. the beam tilting coil 4| determinestheamountby which thebeams are tilted, and hence the disposition of the directionlineflll. I,

With the arrangementiust described one. end of the electron beams is-at all timesinterli lpted by anode material, and only one end of the beams 4 is inthe slot 18 as the beams areswept around by the resolver, so that commutator-electrodes 24 may be employed throughout the full 360 degrees through which the beams are swept. The anode slot l 8 is to this end continuous throughout 360 degrees. If desired, the cathode I4 may be-disposed within the upper anode section I'I instead of the lower anode section l6. Or, if a reduction in sharpness of commutation can be tolerated, pne anqdeportion may be eliminated, and the cathode can be disposed within the remaining portion. One of the electron beams would still be interrupted by anode material, while the. otherbeam would be passed over the upper edgethereof.

In the embodiment oi the invention shown. in Figs...3, ,4. and 5 .thetube 1D 'is disposed, between two dissimilar magnet .poles. 5i .and =52, which are, part of a permanent magnet yoke 53,, The, yoke may belikeneddn effect toa pair. of, horseshoe magnetsdisposed ..with like poles confronting each other .to form thelooprwiththe resulting dissimilar .poles diametrically opposed on the loop. .There results....a.- magnetic flux along the line between the poles El and .52;v If. desired, this flux may be provided, by asingle. U-shapedper: manent, magnet. .The yoke is tiltably. supported in a- U.-shape.d. frame-H54, being; mounted, therein by means of bearings. 55.and.56, fIhe.b ear.--v ings hold .the yoke at .thenonepoleebearing arms 51 and, 58 at points which areintermediatebetween the pole .5! and. 5.2,.on.a line that is-disposed at right. anglestq a.line drawn. between the poles. The bearings 55.,and 56.. are in .turn supported inthe endsofhthe upstanding arms GI and. 62, respectively, of, the. frame .54.; The tube "Us 50 disposedwithin the. yoke 53. and frame 54 that .the,.line ,on which-.the bearing pointslies is perpendicyrlanalso tothe axis of the.t ube.a nd of the. elementstherein :The. U. shapedframeifl is mounted on.-a shaft 63 atits lower mid-point. for rotation about an.axis..coincident. with the tube axis. The shaft B3,.may be rotated by'any desirable means, either manually or through a motor system...

. The. latter embodiment. of the invention is operated .by tilting the yoke. .53.;by. the amount necessarytoplace, one of .the.elec tron beams in the anodeaperture .orslot IB, shown .in Fig. 1, androtating the. shaft 63 at .a desired ,speed'to rotatethepoles 5i and-.52. aboutthe. tube. In and thereby sweep the beam along the slot to make czzgntact with successive commutator electrodes Theelementsofthe .tube 10 may be connected in arutilization circuit. as .shown.in Fig- .6. A battery B .provides a.,, .uniform electron acceler; ating, potential between the anode Hi .and the cathode I l.- The.two. anode portionslB .andJI are connected together. .to..the, positive terminal oi, the battery, while thecathodeis connected to the negative terminah .Signal generators GI G2. G3,-,thesignal currents. from which are to be com-. mutated, are connected atone side .toindividuai commutator electrodes 24 via the, connectin wires,2, and at theotherside to the, cathode H via a common load resistor ,The .common connection maybe completedwthroughthe ground,

as shown, or otherwise if ,desired. The cathode i4 and the commutatorelectrodes 1,4 are thus. all at the same potential in theabsence of-signals f m hes sna enera s. but. .when, theelec:

tron beam establishes,ahconnection between the cathode and aparticular commutator electrode, the signal from the thereto connected generator produces a voltage in th load resistor R. This voltage is furnished to succeeding circuits as the signal output through a capacitor C or any other desired means.

While the invention has been illustrated as applied to an electron tube which functions as a diode as far as the input signals, from the generators GI, G2, G3, are concerned, it is to be understood that the particular number of electrodes employed in the electron tube is not a material part thereof. For the purposes of the present invention it does not matter whether the collector electrodes 24 are diode anodes, or triode grids for controlling signal flow to additional elements which may be added for the purposes of providing amplification, or for any other known desired function of a multielectrode tube.

Many other arrangements and modifications within the scope of the invention will occur to those skilled in the art, and no attempt has been made here to exhaust all the possibilities that come to mind. It is therefore intended that the claims that follow shall be given the broadest possible interpretation consistent with the state of the prior art, and shall not be limited to the particular embodiments of the invention herein illustrated.

Having now described my invention, I claim:

1. An electronic commutator tube device comprising a source of electrons, an accelerating anode surrounding said sOurce and having one endless edge defining a plane to one side of which said source is wholly disposed, means positioned near said source for forming the electrons from said source into a pair of oppositely directed beams substantially normal to said anode, means positioned near the path of said beams for directing one beam over an edge of the anode and the other beam to the anode, and means positioned near said source and including said beamforming means for sweeping said one beam along said edge.

2. An electronic commutator tube device comprising a source of electrons, an accelerating anode surrounding said source and having one endless edge defining a plane to one side of which said source is wholly disposed, means positioned. near said source for forming the electrons from said source into a pair of oppositely directed beams which are normally interrupted by said anode, means positioned near the path of said beams for directing one beam over an edge of the anode, and means positioned near said source and including said beam-forming means for sweeping said one beam along said edge.

3. An electronic commutator tube device comprising a cathode, an accelerating anode surrounding the cathode and being circumferentially apertured to provide a slot lying in a plane which does not include said cathode, means positioned near said cathode for forming the electrons from the cathode into a pair of oppositely directed beams normally directed to unslotted anode material, means positioned near the path of said beams for directing said beams to place the end of one in the slot and to interrupt the other with anode material, and means positioned near said cathode and including said beam-forming means for sweeping said end along said slot.

4. An electronic commutator tube device comprising a cathode, an accelerating anode surrounding the cathode and being circumferentially apertured to provide a slot lying in a plane which does not include said cathode, means positioned near said cathode for forming the electrons from the cathode into a pair of oppositely directed beams normally directed to unslotted anode material, means positioned near the path of said beams for directing said beams to place the end of one in the slot and to interrupt the other with anode material, means positioned near said cath ode and including said beam-forming means for sweeping said end along said slot, and means positioned exteriorly of said anode in the vicinity of said slot to intercept electrons therefrom.

5. An electronic commutator tube device comprising a cathode, an accelerating anode surrounding the cathode and being circumferentially apertured to provide a slot lying in a plane which does not include said cathode, a plurality of electrodes surrounding the anode positioned near said slot, means positioned near said cathode for forming the electrons from the cathode into a pair of oppositely directed beams normally directed to unslotted anode material, means positioned near the path of said beam for directing said beams to place the end of one in the slot and to interrupt the other with anode material, and means positioned near said cathode and including said beam-forming means for sweeping the said one beam along the slot to contact successive ones of said electrodes.

6. An electronic commutator tube device comprising a cathode, a cylindrical accelerator anode concentrically surrounding the cathode, said anode being circumferentially apertured to provide a circumferential slot extending completely around the anode defining a plane to one side of which the cathode is wholly positioned, a plurality of electrodes arrayed side by side about the outside of the anode positioned near the slot, means positioned near said cathode for forming the electrons from the cathode into a beam extending generally diametrically across the anode and hence directed to unslotted anode material, means positioned near the path of said beam for directing the beam in a tilted path and thereby maintain only one end thereof in the slot while maintaining the other end directed to unslotted anode material, and means positioned near said cathode and including said beam-forming means for sweeping said one end along the slot to contact successive ones of said electrodes.

7. An electronic commutator tube device comprising a cathode, a cylindrical accelerator anode concentrically surrounding the cathode, said anode being circumferentially apertured to provide a circumferential slot extending completely around the anode defining a plane to one side of which the cathode is wholly positioned, a plurality of electrodes arrayed side by side about the outside of the anode positioned near the slot, means positioned near said cathode for forming the electrons from the cathode into a beam extending generally diametrically across the anode and hence directed to unslotted anode material, means positioned near the path of said beam for directing the beam in a tilted path and thereby maintain only one end thereof in the slot whil maintaining the other end directed to unslotted anode material, and means positioned near said cathode to rotate the beam about the axis of the tube to sweep said one end along the slot.

8. An electronic commutator device comprising an electron tube having a cathode, an accelerating anode surrounding the cathode, said anode being circumferentially apertured to provide a circumferential slot extending completely around the anode defining a plane to one'side of which the cathode is wholly positioned, a plurality of electrodes arrayed side by side about the anode positioned near the slot, and an envelope surrounding the electrodes, electromagnetic means positioned outside the envelope for forming the electrons from the cathode into a beam-extending across the anode and hence directed to unslotted anode material, means positioned near the path of said beam for directing the beam 'in a tilted path and thereby maintain only one-end thereof in'the slot, and means positioned-outside the envelope and employing saidelectromagnetic means for sweeping said end along the slot.

9. An electronic commutator device comprising: an electron tube'having a cathode, an accelerating anode surrounding the cathode, said anode being circumferentially apertured to provide a circumferential slot extending completely around the anode defining a plane to one side of which the cathode is whollypositioned, a plurality of electrodes arrayed side by side about the outside of the anode adjacent the slot, and an'envelope surrounding the electrodesfa pair of dissimilar magnetic poles positioned one on each side of the tube for forming the electrons from the cathode into a beam extending 'across' the anode, means mounting said poles tiltably about an axis disposed perpendicularly to both the axis of the tube and the line between the poles, and meansfor effecting relative rotation between the polesand the tube about'the tube axis.

10. An electronic commutator device comprising: an electron tubehaving a cathode, an accelerating anode surrounding the cathode, said anode beingcircumferentially apertured to provide a circumferential slot extending completely around the anode defining a'pla'ne'to one side of which the cathode is wholly'positioned, -a plurality of'elec'trodes arrayed side by side about the anode adjacent the slot, and anenvelope surrounding the electrodes; -a magnetic core having two opposed "confronting dissimilar poles, disposed about'the'tube with onepole on each side thereof, a bifurcated frame tiltably mouritmg the core at two diametrically opposed points intermediate the poles and lyingon-a line per-- pendic'ular to both the tube axis and the line between the poles, and means for rotating the frame on the tube-axis. 11. An electronic commutator device comprising: an electron'tube having a 'catho'de',*anaccelerating anode concentrically surrounding the cathode, said anode being circumfere'ntiallyapertured to provide a circumferential slot extending completely around the anode defining a" plane to one side of which 'the cathode iswholly positioned, a plurality of electrodes arrayed 'si'de'by :side about the-outside of the'anode adjacent the slot, and an envelope surrounding the elctrodesr a multip'olar electromagnetic resolver 'surrounding the tube for'formin'g'the electron stream from the cathode into a beam extending across the anode directed to unslotted anode-material, and adapted for energization from a 'multiphase 'source of alternating current for rotatingthe beam aboutthe axis of the tube to sweep the ends thereof circumferentially about the "interior of the anode; and a'solenoidal coil surrounding the tube and adapted to be-energized'to provide a steady magnetic flux in thetube paralleltothe axis thereof, whereby the beam-may be directed toward parallelism with said axis to maintain only one end thereof in the slot while maintainin the other end directed to unslotted anode material.

12. An electronic commutator device comprising: an electron tube having a cathode, an accelerating anode surrounding thecathode, said anode being circumferentially apertured to provide a circumferential slot extending completely around the anode defining a plane to one side of which the cathode is wholly positioned, a plurality of electrodes arrayed side by side about-the outsideof the anode adjacent the slot, and envelope surrounding the electrodes asolenoidal coil wound around the sides.- of the tube; and-a fourpole electromagnet adapted for energization withi'alternatingcurrent in phase quadrature, surrounding the tube at-the sides. A

13, An electron tube having; in order, a cathode, an electron accelerator electrode, and -a collector eleotrode,spaced apart generally'in a first direction; said accelerator electrode having a passage therethrough for the passage of electrons; said cathode being of restricted sizeand disposed wholly to one side of said passage with "respect to 'said'flrst direction;-whereby only those electrons which travel substantially in -a second direction angularly disposed with respect to said first direction can reach said collector electrode.

14. 'An'electronic commutator tube device comprising-a source of electrons, a, cylindrical accelerating anode surrounding said source and having one endless edge defining aplane to one side of which said source is wholly disposed,- means adjacent said source for forming the electronsfrem said source into a pair of oppositely directed beams normal to said anode, andmeans adjacent the path of said beams for tilting the direction of said beams to direct one beam over said-edge while maintaining the other beam directed to said anode.

15. An electronic commutator tube device comprising a source of electrons,an acceleratin anode surrounding said source and-having one endless edge defininga plane to one-side of which said-source is wholly disposed; means adjacent said source for forming the electrons from said source into apair of "oppositely directed :beams normally impinging entirely upon said anode, and means adjacent the path-of said beams for tilting said beams into a new directioninwhich one beam isdirected over said edge and the other beam continues'to be directed to said anode.

I 16. An electronic commutator tube device comprising a source of electrons, a cylindricalacceler'atin'g anode surrounding said source and having 'one endless edge defining a'plane to 'one'side of which said"source'is whollydisposed', means adjacent said source for forming the electrons from said source into a pair of oppositely directed beams normal to saidanode, and means adjacent the path of said-beams for directing'one "of said beams over said edgewhile maintaining the other 'beam directed to said'anode.

LAURENCE BATCHIELDER. References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,851,549 Thompson Mar. 29, 1932 2,082,327 Dummont 'June 1, 1937 2,217,774 Skellett Oct. 15,1940 2,324,089 Johnson July 13, 1943 2,352,657 Potts "July- 4, 1944 2,433,403 Skellett Dec. 30, 194'? 2,440,639 'Marmont Apr. 27, 1966 2,552,363 Bath May 8, :195-1 

